1. Field of the Invention
The present invention relates to the field of portable and manually operated pumps and in particular relates to an inflatable air pump and a method for making the same.
2. Description of the Prior Art
It is well known in the prior art to use or incorporate a collapsible and flexible bellows in an air mattress and to simultaneously use the bellows as a pillow portion of the mattress. The incorporation of a flexible and collapsible bellows is illustrated by W. H. Hurt, "Pneumatic Mattress", U.S. Pat. No. 3,042,941.
It is also well known to incorporate a bellows within other portions of the mattress, such as the foot or corner as shown in J. M. Pinkwater, "Air Pump for Inflatable Structures", U.S. Pat. No. 3,068,494; E. S. Forsberg, "Pump For Air Mattresses", U.S. Pat. No. 3,112,502; and R. J. Edwards, "Compartmented Bag Having Selected Inflation Controls", U.S. Pat. No. 3,583,008.
However, such prior art pumps or bellows have incorporated either an internal means for giving the bellows resiliency, such as shown by Marcus, supra; Forsberg, supra; and Edwards, supra; or have relied upon the use of a material for the walls of the bellows which is inherently self-supporting and resilient such as used by Hurt, supra; Houghton, "Inflatable Bed or Mattress and the Like", U.S. Pat. No. 2,068,134; and Pinkwater, supra.
The result in each case is an air pump for inflatable mattresses or other inflatable structures which pump is relatively heavy and non-collapsible.
Reference may also be made to G. D. Black U.S. Pat. No. 3,063,620 entitled Self-Expandable Bag, showing a self-expandable bag for use in administering inhalant gas to a patient.